The present invention relates generally to agricultural implements and more particularly to a locking structure for the rear furrow wheel of a disk tiller.
A conventional disk tiller includes an elongated frame adapted to be pulled at an angle to the direction of travel and a plurality of ground-working disks mounted along the rear side of the frame and adapted to be raised and lowered into engagement with the ground.
The frame is supported relative to the ground by a front and a rear furrow wheel adapted to travel in furrows left by the disks and a land wheel carried near the rear of the machine and forwardly of the frame. Because disk tillers and the like typically have a substantial working width, provision in the design must be included to enable the implement to trail in a substantially narrowed configuration.
Conventional rear furrow wheel arrangements generally provide for locking of the rear furrow wheel in a desired angular relationship to the frame during operation.
One method commonly used to narrow the implement from its operating width provides for swinging the rear furrow wheel to a different angular position relative to the main frame so that the tail portion of the implement trails directly behind the tractor or towing vehicle.
In U.S. Pat. No. 2,779,261 to Northcote et al, provision is made to adjust the angular position of the furrow wheel support beam and furrow wheel relative to the main frame. The adjustment is effected by swinging the wheel support beam about a vertical pivot on the main frame and locking it in place with bolts inserted through openings of vertically spaced, horizontally disposed brackets carried on the main frame. This method of changing and securing the rear furrow wheel in a new angular position relative to the main beam can demand a significant amount of operator time.
Another method of locking the rear furrow wheel in its transport position is found in U.S. Patent 3,700,042 to Patterson et al. Patterson provides a locking structure to secure the rear furrow wheel in a transport position and a yieldable structure permitting the furrow wheel to swing in response to abnormal side loads on the wheel. The structure provided for in Patterson et al is composed of many parts and consequently is expensive to manufacture and maintain.